Method and system for location management and location information providing system

ABSTRACT

In an information providing system, a user inputs desired mobile ID number to a client terminal. The client terminal transmits a request for location information on the mobile station including the mobile ID number to a location server via a location information server. The location server transmits a request for object movement information corresponding to the mobile station to an object information server. The location information server obtains the information from a traffic control device. Location information on the mobile station obtained by the location information server is transmitted to the terminal.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method and a wireless communicationsystem for managing information on locations of mobile stations and alocation information providing system.

2. Description of the Related Art

In the conventional mobile communication system, a device for managinglocation of a plurality of mobile stations is provided, to storeinformation about which area (called “location area”) each of mobilestations is located. When an incoming call directed to a mobile stationoccurs, the device identifies the location area. Next, the devicegenerates paging signal to transmit to the mobile station via a switchcovering the location area and one of the base stations belonging to theswitch.

In the registration of a location area, firstly a mobile stationreceives information on location area Secondly, the mobile stationtransmits a number to identify the mobile station and the location areainformation, via the base station and the switch. Especially, there is alocation management system of a mobile station in a train. In such asystem, a communication device is provided in a train, to collectivelymanage location registration of all mobile stations in the train(reference will be made to Japanese Patent Application No. H11-355835).

However, it is cumbersome and costs a lot to provide such device in atrain capable of processing requests of location registration from manymobile stations. Even if such devices are introduced, base stations andswitches still must process large amounts of request especially in anurban city where many trains run. Specifically, radio channels have tobe allocated to exchange signals for location registration between alocation registration server and mobile stations. Therefore, radiofrequency bandwidth available for voice and data communication isrestricted thereby communication traffic volume increases. It is oftenthe case that a moving object such as a train or a bus moves to a placesuch as a tunnel into which a radio wave transmitted from a base stationdoes not propagate. In this case the base station does not receives anysignals either from the object and a mobile station in the object, sothat the location server cannot recognize a location of the mobilestation.

There is a system for providing location information stored in thelocation server to an external terminal. In such a system, a location ofa mobile station can be tracked in real-time. In principle, it ispossible to know a future location of a mobile station as long as a userof the mobile station get off a train. However, in the conventionalsystem such information on future location cannot be provided.

The present invention, as its object, provides a wireless communicationsystem at a low cost, in which locations of mobile stations movingtogether with an object such as trans and buses are tracked accuratelyand efficiently. In addition, the present invention provides acommunication system for providing a future location of a mobile stationto a third party.

To attain the above object, a method of the present invention formanaging location information on a mobile station in an object by aserver on a mobile network comprising the steps of:

upon receiving object identification information from a transmittingdevice provided in the object, the mobile station transmitting to theserver received object identifying information and mobile identifyinginformation for identifying the mobile station; the server receiving andstoring correspondingly the object identifying information and themobile identifying information;obtaining, from a traffic control device which controls movement of theobject, object movement information of the object identified by theobject identifying information; converting the movement information intoa location area information; andmanaging location of the mobile station on the basis of the locationarea information.

In this method, a location of mobile station is tracked by transmittinga pair of mobile identifying information and object identifyinginformation. It is not necessary to provide an expensive device, whichcan deal with registration requests from many mobile stations in anobject at one time. It is only an inexpensive device for merelytransmitting the object identifying information that is needed. Thus,this system can be established in at low cost. In a preferableembodiment upon receiving a call for the mobile station, the serverinquires about the movement information for the traffic control device.In another preferable embodiment the traffic control device notifies theserver of the movement information when detecting movement of theobject.

A method for communication in a communication system of the presentinvention having a server on a mobile network for communication with amobile station and a traffic control device for controlling an objectcomprises the steps of: upon receiving an object identifying informationfor identifying the object from a transmitting device provided in theobject, the mobile station transmitting to the server mobile identifyinginformation for identifying the mobile station and received objectidentifying information; and

the server receiving the mobile identifying information and the objectidentifying information;storing the mobile identifying information and the object identifyinginformation correspondingly;when receiving a call for the mobile station identified by the mobileidentifying information, retrieving the object identifying informationcorresponding to the mobile identifying information; andtransmitting retrieved object identifying information to the trafficcontrol device; andthe traffic control device generating movement information on the objectidentified by the object identifying information; andtransmitting generated movement information to the server; andthe server converting received movement information into location areainformation; andpaging the mobile station on the basis of the location area information.

By using this method, it is not necessary to update registration oflocation every time a mobile station moves into another location area,once the object identifying information is registered with the server.Therefore, radio traffic according to location registration is reduced.

In another embodiment, upon detecting a movement change of the object,the traffic control device generates movement information, transmits tothe server the object identifying information and generated movementinformation. And the server receives the movement information, convertsreceived movement information into location area information about anarea within which the mobile station is located and stores the objectidentifying information and the location area informationcorrespondingly. When receiving a call for the mobile station includingthe mobile identifying information, the server retrieves the locationarea information corresponding to the mobile identifying information andpages the mobile station on the basis of the location area information.

In this embodiment, the location server keeps the latest location areainformation on a mobile station. Therefore, the location server does notnecessarily request movement information to the traffic control device,when a call for a mobile station is issued. Thus, identifying the mobilestation to transmit a paging signal can be done quickly.

A communication system of the present invention has a traffic controldevice for controlling movement of an object and a mobile network. Themobile network comprises a mobile station, a base station forcommunicating with the mobile station, a switch for communicating withthe base station, a location server for communicating with the switch,and an object information server for communicating with the locationserver and the traffic control device. The mobile station comprisesmeans for receiving object identifying information for identifying theobject and transmitting to the base station received object identifyinginformation and mobile identifying information for identifying themobile station. The location server comprises means for storing theobject identifying information and the mobile identifying informationcorrespondingly, both of which sent from the mobile station, means forretrieving and transmitting to the location server the objectidentifying information corresponding to the mobile identifyinginformation, when receiving from the switch an inquiry of location areainformation on the mobile station including the mobile identifyinginformation and means for receiving from the object information serverand transmitting to the switch the location area information on theobject identified by the object identifying information. The objectinformation server comprises means for receiving from the locationserver and transmitting to the traffic control device the objectidentifying information, means for receiving from the traffic controldevice movement information on the object identified by the objectidentifying information, means for converting received movementinformation into the location area information and means fortransmitting converted location area information to the location server.The traffic control device comprises means for receiving from the objectinformation server the object identifying information and generating themovement information on the basis of received object identifyinginformation and means for transmitting generated movement information tothe object information sever.

In a preferable embodiment, the traffic control device comprises meansfor detecting movement change of the object and generating movementinformation representing movement of the object and means fortransmitting to the object information server the object identifyinginformation and the movement information. The object information servercomprises means for receiving from the traffic control device the objectidentifying information and the movement information and convertingreceived movement information into location area informationrepresenting an area within which the mobile station is located andmeans for transmitting to the location server the object identifyinginformation and the location area information. The location servercomprises a first storing means for receiving from the objectinformation server and storing correspondingly the object identifyinginformation and the location area information, a second storing meansfor storing correspondingly the object identifying information and themobile identifying information, both of which sent from the mobilestation and means for retrieving from the second storing means theobject identifying information corresponding to the mobile identifyinginformation, when receiving from the switch an inquiry of the locationarea information including the mobile identifying information.

Furthermore, it is possible that when not receiving from thetransmitting device the object identifying information and moving intoanother location area, the mobile station transmits to the locationserver updated location information on the mobile station and the mobileidentifying information. In addition, when receiving the location areainformation and the mobile identifying information sent from the mobilestation, the location server stores to the second storing means themobile identifying information and the updated location area informationcorrespondingly, instead of the object identifying information.

An information providing system of the present invention for providinglocation information on a mobile station in a mobile network to aterminal comprises a location server in the mobile network for managinglocation of the mobile station and a location information server forcarrying out communication with the terminal. Upon receiving from atransmitting device provided in an object identifying information foridentifying an object, the mobile station transmits to the locationserver the mobile identifying information for identifying the mobilestation and received object identifying information. The location serverreceives and stores correspondingly the object identifying informationand the mobile identifying information sent from the mobile station.Upon receiving from the terminal an inquiry of location information onthe mobile station including the mobile identifying information, thelocation information server judges whether the object identifyinginformation corresponding to the mobile identifying information isstored in the location server. If the object identifying information isstored, transmits to the terminal boarding information representing thatthe mobile station is in the object. By using the terminal in thissystem, a person can know that the mobile station is in the object.

In a preferable embodiment, the location information server furthercomprises means for identifying the mobile station using the mobileidentifying information, carrying out communication with the mobilestation, and obtaining from the mobile station the location informationand transmitting to the terminal the boarding information and thelocation information.

In another preferable embodiment, the information providing systemfurther comprises an object information server for carrying outcommunication with a traffic control device which controls movement ofthe object. Upon receiving from the terminal an inquiry of locationinformation including the mobile identifying information, the locationinformation server transmits the mobile identifying information to thelocation server. Also, upon obtaining from the location server thelocation information, the location information server transmits to theterminal the boarding information and the location information. Uponreceiving from the location information server the mobile identifyinginformation, the location server transmits to the object informationserver the object identifying information corresponding to the mobileidentifying information. Upon receiving the object identifyinginformation from the location server, the object information serverobtains from the traffic control device the movement information on theobject corresponding to the object identifying information, convertsobtained movement information into the location information, andtransmits the location information to the location information servervia the location server.

It is possible that when receiving from the terminal an inquiry of thelocation information on the mobile station, the location informationserver generates, on the basis of the movement information, estimatedlocation information representing a future location on the mobilestation and transmits the estimated location information to theterminal. In this system a person can obtain a future location of amobile station in addition to the present location.

In another preferable embodiment, the object information server storesthe movement information obtained from the traffic control device andthe object identifying information correspondingly. When receiving fromthe location server the object identifying information, the objectinformation server generates the location information on the objectidentified by the object identifying information on the basis of storedmovement information on the object.

It is possible that upon detecting a movement change of the object, thetraffic control device updates and notifies to the object informationserver of the movement information. Also, the object information serverreceives the movement information and generates the location informationon the basis the movement information.

A method of the present invention for providing location information ofa mobile station in a mobile network to a terminal comprises the stepsof:

the mobile station receiving, from a transmitting device provided in anobject, object identifying information for identifying the object;transmitting to a server in the mobile network the object identifyinginformation and mobile identifying information for identifying themobile station;the server storing the object identifying information and the mobileidentifying information correspondingly;when receiving from the terminal an inquiry of location information onthe mobile station including the mobile identifying information, judgingwhether the object identifying information corresponding to the mobileidentifying information is stored in the server; andif the object identifying information is stored, generating andtransmitting to the terminal boarding information representing that themobile station is in the object.

In a preferable embodiment, the server stores the object identifyinginformation and the mobile identifying information correspondingly. Whenreceiving from the terminal an inquiry of location information on themobile station including the mobile identifying information, the serverretrieves the object identifying information corresponding to the mobileidentifying information, obtains movement information on the objectidentified by the object identifying information, converts obtainedmovement information into the location information and transmits thelocation information to the terminal.

It is possible that when receiving the movement information, the servergenerates, on the basis of the movement information, estimated locationinformation representing a future location of the mobile station andtransmits the estimated location information to the terminal.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is shows a communication system based on the first embodiment

FIG. 2 is a schematic diagram of a location server in the system.

FIG. 3 shows a detail of a location table in the system.

FIG. 4 is a schematic diagram of an object information server in thesystem.

FIG. 5 is a sequence diagram of the system.

FIG. 6 is a schematic diagram of an object information server used for acommunication system based on the second embodiment.

FIG. 7 shows details of a first and a second location table of thelocation server.

FIG. 8 is a sequence diagram of the system based on the secondembodiment.

FIG. 9 is an information providing system based on the third embodiment.

FIG. 10 is a schematic diagram of an information server in the system.

FIG. 11 is schematic diagram of a mobile station.

FIG. 12 is a sequence diagram of the system.

FIG. 13 is a schematic diagram of an object management device in aninformation providing system based on the fourth embodiment.

FIG. 14 shows a detail of a management table of the object informationserver.

FIG. 15 is a sequence diagram of the information providing system basedon the fourth embodiment.

DETAILED DESCRIPTION

Reference will now be made in detail to the preferred embodiments of theinvention, examples of which are illustrated in the accompanyingdrawings.

1. First Embodiment 1-1. Configuration of a Communication System ofFirst Embodiment

FIG. 1 illustrates a wireless communication system based on the firstembodiment of the invention. As shown in FIG. 1, the system comprises amobile network NET, a moving object 2, and a traffic control device 30.

Object 2 is, for example, a train, a bus, and other means oftransportation. It will now be described assuming that Moving object isa train. In the figure only a moving object 2 is illustrated but inactuality, many trains 2 exist in the system. Traffic control device 30manages movements of the trains. Traffic controls device 30 keeps trackof each train, specifically, has present location, train schedule, andother information related to the train such as delay. Also, Trafficcontrol device 30 generates movement information INFx, which is thelatest information on a movement of an object, to transmit otherdevices.

Movement information INFx includes object location information INF1 on alocation of Object 2 and related information INF2 for the movement.Specifically, a form of location information INF1 takes a form of“Longitude, Latitude” or “Name of line, Distance from neighboringstation, Direction”. For example, the detail of Location informationINF1 is “Long. 136° 15′ E., 35° 45′ N.”, or “Tokaido line, 2 km fromShinagawa, to Yokohama”. Related information INF2 includes a name of atrain such as “Hikari No. 10” and a delay or suspension.

Mobile communication network NET has a plurality of base stations 3-1,3-2, . . . ; a plurality of switches 4-1,4-2, . . . ; object informationserver 40A; and location server 50A. Location server 50A manageslocation area information of all mobile stations it covers.

Each of base stations 3-1, 3-2, . . . is provided at a certain distancefrom neighboring one and covers a base station areas 4 s each lettered“4 a” through “4 f” as shown in FIG. 1. In other words, each of basestations can carry out radio communication with mobile stations withinone of base station areas 4 it covers. As shown, each of base stations3-1 through 3-6 covers each of Base station areas 4 a through 4 f. EachLocation area 5 lettered 5A and 5B is a compilation of base stationareas 4 s. Each of Switches 4-1,4-2, . . . covers one of Location areas4.

Object 2 has a transmitting device TD and moves on a railroad L.Railroad L extends across boundaries of Location areas 5. Transmittingdevice transmits an object ID number IDt by radio. Each of Objects 2 hasa unique object ID number IDt. Each of Mobile stations 1 stores a uniquemobile ID number IDm to identify a mobile station uniquely. Mobile IDnumber is, for example, a phone number.

When a user of Mobile station 1 is not in a train, Mobile station 1receives and stores Location area information INF from Base station 3.When Mobile station 1 moves into another Location area 1, Mobile station1 notifies Location information INF and Mobile ID number IDm to mobilecommunication network NET via Base station 3. When a user of Mobilestation 1 gets aboard Object 2, Mobile station 1 receives Object IDnumber IDt from Transmitting device TD and notifies Mobile ID number IDmand received Object ID number IDt to mobile communication network NETvia Base station 3.

Specifically, Mobile station 1 keeps watching on reception of Object IDnumber IDt. Only when Mobile station receives Object ID number IDt,Mobile ID number IDm and Object ID number IDt are transmitted to Mobilecommunication network NET. In other words, Location area information INFis not transmitted during the ride. This results in a reduction offrequency of transmission of information on location about a mobilestation that is necessary for a registration.

1-2. Configuration of Location Server 50A

As shown in FIG. 2, Location server 50A has a control unit 51 and alocation table TBL. Control unit 51 reads from or writes to Locationtable TBL data. In addition, Control unit 51 carries out communicationwith Object information server 40A and Switch 4, to manage locations ofall Mobile stations 1 in Mobile communication network NET. In addition,Location server 50A generates paging signal when an incoming call forMobile station 1 is issued.

FIG. 3 shows information stored in Location table TBL. Location tableTBL has a plurality of records Rb1, Rb2, . . . , in each of which aMobile ID number IDm and location information of a mobile station arestored. The location information is either Location information INF oran Object ID number. Specifically, when a Mobile station 1 is in a trainObject ID number IDt is stored, while when not in a train Location areainformation INF is stored.

For example, if a mobile station whose Mobile ID number IDm is “X0001”,is in Object 2 whose Object ID number is “A01234”, “X00001” and “A01234”are stored in Rb1 of Location table TBL correspondingly as shown in FIG.3. If a mobile station whose Mobile ID number is “X0003” is not inObject 2, Mobile ID number “X00003” and Location area information INF“5B” are stored correspondingly in a record Rb3.

1-3. Configuration of Object Information Server 40A

FIG. 4 is a schematic diagram of Object information server 40A. Asshown, Location information server has a control unit 41 and a convertunit 42. Control unit 41 carries out communication with Traffic controldevice 30 and Location server 50A as well serves as nerve center ofObject information server 40A. Convert unit 42 converts Object locationinformation INF1 included in Movement information INFx sent from Trafficcontrol device 30 into Location area information INF.

In one example, Convert unit 42 has a first table for storing Locationarea information INF and locations represented by latitude and longitudecorrespondingly, and a second table for information on routes of trainsand Location area information INF. Upon obtaining Movement informationINF1 in a “Latitude, Longitude” form, Convert unit 42 retrieves from thefirst table Location area and outputs to Control unit 41 informationcorresponding to object location information INF. In case of receptionof Movement information INF1 in a “Line name, Distance from neighboringstation, Direction” form, Convert unit 42 retrieves from the secondtable and outputs to Control unit 41 a present location of Object 2corresponding to the Object location information INF1.

It is noted that although Object location information INF1 could takevarious forms, conversion of any types of Location area information INF1can be effected by Convert unit 42.

14. Operation of the System

One example of operations of a wireless communication system of theinvention will now be described referring to the drawings. FIG. 5 is asequence diagram of the communication system. When Mobile station 1comes into Object 2, the Mobile station 1 receives an Object ID numberIDt sent from Transmitting device TD (step S1) and transmits to Locationserver 50A registration request including the Object ID number IDt and aMobile ID number IDm via Base station 3 and Switch 4 (not shown) (stepS2). When Location server 50A receives the registration request, theObject ID number IDt and the Mobile ID number IDm are extracted from therequest and stored in Location table TBL (step S3).

For example, if the Mobile ID number IDm is “X0002” and the Object IDnumber is “A01234”, “X0002” and “A01234” are stored correspondingly inRb2 of Location table TBL as shown in FIG. 3.

It is noted that even when a Mobile station 1 comes across a borderbetween location areas, the Mobile station 1 does not transmit Locationarea information as long as the Mobile station 1 is in an object therebykeeps receiving Object ID number IDt.

When one of Switches 4 receives a call for Mobile station 1, the Switch4 issues a location request REQ1 to Location server 50A (step S4). REQ1includes Mobile ID number IDm of the Mobile station 1. When Locationserver receives Location request REQ1, Control unit 51 retrieves fromLocation table location information corresponding to the Mobile IDnumber (step S5). Control unit 51 judges whether received locationinformation is Location area information INF or Object ID number IDt.

If Control unit 51 retrieves Location information INF, Control unit 51transmits retrieved Location information INF to the Switch 4. In thiscase, Location server 50A generates and transmits to Object informationserver 40A location request REQ2 (step 6).

Object information server 40A generates and transmits to Traffic controldevice 30 a movement request REQ3 including the Object ID number IDt(step S7). Traffic control device 30 firstly converts received Object IDnumber IDt into a certain number available for Traffic device 30 andsecondly generates Movement information INFx. Net, Traffic controldevice 30 transmits Movement response RES3 including the Object IDnumber IDt and the Movement information INFx to Object informationserver 40A (step S8).

Object information server firstly 40A converts Object locationinformation INF1 included in received Movement information INFx intoLocation area information INF (step S9) and next transmits a locationarea response RES2 including the location area information INF and theObject ID number IDt to Location server 50A (step S10).

After the reception of Location area response RES2, Location server 50Atransmits to Switch 4 a location area response RES1 including thelocation area information INF and the Object ID number IDt (step S11).Switch 4 issues a paging request including the Mobile ID number to Basestations 3 within a location area designated by the Location areainformation INF. When the Mobile station answers, the connection isestablished.

In this system a mobile station does not notify location areainformation to any nodes in a mobile network during the ride. Therefore,the load on the network is reduced thereby improves system performance.

In addition, a communication device capable of registering many mobilestations in a train at one time is not necessarily introduced. The onlydevice provided in a train is one for transmitting an ID number byradio. Therefore, this system can be established at a low cost. Inaddition, since Convert unit is introduced to convert Movementinformation INFx into Location area information INF, information onlocation of a train can be managed regardless of data format of objectlocation information which a traffic control device has.

2. Second Embodiment 2-1. Configuration of a Communication System

A wireless communication system based on the second embodiment issimilar to that of the first embodiment, except that a location server50B is introduced instead of Location server 50A.

FIG. 6 is a schematic block diagram of Location server 50B. As shown,Location server 50B has a control unit 51, first location table TBL1,and second location table TBL2. Second location table TBL2 is the sameas Location table of the first embodiment FIG. 7 shows details of theFirst location table and Second location table. First location tableTBL1 has a plurality of records Ra1, Ra2, . . . , each storing Object IDnumber IDt and location area information INF correspondingly. It isnoted that the records and Objects 2 are same in number. For example, ifObject 2 is located within a location area 5A and Object ID number IDtis “A01234”, “A01234” and “5A” are stored in a record Ra1 of Firstlocation table TBL1 as shown in FIG. 7.

In this system upon updating movement information INFx on an Object 2,Traffic control device 30 transmits the updated information to Objectinformation server 40A. Object information server 40A firstly convertsreceived information INFx into Location area information INF andsecondly transmits the converted information INF to Location server 50B.Location server 50B receives and stores to First location table TBL1 theMovement information INFx. In this way information stored in Firstlocation table TBL1 is updated. Information stored in Second locationtable TBL2 is updated by notification from Mobile station 1, asdescribed in the first embodiment.

2-2. Operation of the System

Operations of the wireless communication system based on the secondembodiment will now be described referring to FIG. 8. As shown, steps S1through S3 are the same as those of first embodiment.

When Traffic control device 30 updates Movement information INFx,Traffic control device 30 transmits a movement notice N1 including anObject ID number and updated information INFx to Object informationserver 40A (step S21). When receiving Movement notice N1, Objectinformation server 40A converts Object location information INF1included in the Movement information INFx into Location area informationINF (step S22). Next Object information server 40A generates andtransmits to Location server 50B an Area notice N2 (step S23).

Suppose here that Object 2 is “Tokaido Line” moving from Shinagawastation to Yokohama station and Shinagawa and Yokohama station arelocated within “5A” and “5B”, respectively. When the train arrives atYokohama station, Traffic control device 30 generates Object locationinformation INF1 indicating a stop of the tram at Yokohama station.Next, Traffic control device 30 transmits Movement notice N1 includingthe information INF1. Object information server 40A receives Movementnotice N1. Convert unit 42 converts INF1 into Location area informationINF. Control unit 41 generates and transmits to Location server 50B Areanotice N2 including an Object ID number IDt and the location areainformation INF.

Location server 50B receives the Area notice N2 and updates locationarea information INF corresponding to the Object ID number IDt stored inFirst location table TBL1 (step S24). Specifically, if Object ID numberIDt is “A01234”, Location area information INF in record Ra1 is updatedfrom “5A” to “5B” shown in FIG. 7. In this way First table TBL1 has thelatest information on movement.

In other words, Object information server 40A does not ask Trafficcontrol device for movement information when a call for Mobile station 1in Object 2 is issued. Therefore, Location server 50B is able to obtainlocation area information on the mobile station quickly, thereby Switch4 is able to route incoming calls effectively.

3. Third Embodiment

An information providing system based on the third embodiment is anapplication of the system based on the second embodiment.

3-1. Configuration of the System

FIG. 9 is a schematic diagram of the system of this embodiment. Thissystem differs from that of the second embodiment only in having aLocation information server 60, Client terminal 70, and Mobile station1A instead of Mobile station 1. Client terminal 70 is, for example, aPersonal Computer (PC), Personal Digital Assistants (PDA), mobile phone,and other communication devices, which carry out communication withLocation information server 60.

FIG. 10 is a schematic block diagram of Location information server 60.As shown, Location server has a Central Processing Unit (CPU) 61, ReadOnly Memory (ROM) 62, Random Access Memory (ROM) 63, Interface 64, andHard disk 65. Location information server 60 provides locationinformation of Mobile station 1A responsive to a request from Clientterminal 70.

Specifically, CPU61 controls all the functions of all devices inLocation information server 60 and executes applications. ROM62 stores,for example, a boot program. RAM 63 temporarily stores data orapplication programs for CPU61. Hard disk 65 stores applicationprograms, which are a communication program for the communication withClient terminal 70 and Location server 50B, an estimation program forthe estimation of a future location of Object 2, and a call program forcalling Mobile station 1 on the basis of Location area information INF.Bus 150 links all devices.

Mobile station 1A differs form Mobile station 1 in having functions ofgeneration and transmittance of location information. FIG. 11 is aschematic diagram of Mobile station 1A. As shown, Mobile station 1A hasa control unit 100, Global Positioning Systems (GPS) receiver 110, radiodevice 120, input device 130, Liquid Crystal Display (LCD) 140, and Bus150. GPS receiver 110 receives radio wave sent by a satellite andgenerates information on the present location of Mobile station 1Aincluding the longitude and latitude. Radio device 120 carries out radiocommunication with Base station 3 under control of CPU61. Input device130 has buttons including Push Button (PB) and cursor keys and sendsinformation on a user's direction into Control unit 100. LCD 140displays information. Control unit 100 has a CPU 111, ROM 112, RAM 113,and EEPROM 114; and controls all the functions of all devices in Mobilestation 1A. ROM 112 has application programs for the control of devices,communication with Location information server 60, and generation ofrelated information.

The related information includes, for example, a direction and velocityof Object 2. RAM 113 temporarily stores data and application programsfor CPU 111. EEPROM 114 nonvolatile memory and stores updatedapplication programs. Bus 150 electrically connects all devices.

3-2. Operation of the System

FIG. 12 is a sequence diagram of the information providing system. It isnoted that this system carries out procedures for updating location areainformation INF, which is the same as that in the second embodiment.

A user operates Client terminal 70 with Input device 130 to accessLocation information server 60. Client terminal 70 displays in LCD 140direction for input of Mobile II) number. When the user input a MobileID number IDm (phone number, for example), Client terminal 70 transmitsto Location information server 60 location request REQ 4 including theMobile ID number IDm (step S31).

Upon receiving location request REQ 4, Location information server 60transmits location request REQ 5 including the Mobile ID number toLocation server 50B (step S32). Location server 50B receives locationrequest REQ5 and retrieves location area information INF correspondingto the Mobile ID number IDm from First location table TBL1 and Secondlocation table TBL2 (step S33). Furthermore, if Object ID number IDt isstored in Second Location table TBL2, Location server set a flag FLG to“1”. If Object ID number IDt is not stored, the flag FLG is set to “0”(step S33).

Next, Location server 50 transmits to Location information server 60 alocation request RES 5 including the Location area information INF andFlag FLG (step S34). Location information server 60 receives Locationresponse RES 5 and executes the estimation program, to page Mobilestation 1A (step S35). Specifically, Location information server pages,via a Switch, Base stations 3 located within an area identified by theLocation area information INF, by sending a paging signal includingMobile ID number. In addition, if Flag FLG is set to “1”, Locationinformation server 60 generates boarding information indicating whethera user of Mobile station 1A takes on a train. If Flag FLG is set to “0”,the boarding information is not generated.

Upon receiving the paging signal, Mobile station 1A generates andtransmits to Location information server 60 location information on thepresent location and related information including a direction andvelocity (step S36).

Location information server 60 receives the location information and therelated information from Mobile station 1A and transmits the locationinformation, related information, and the boarding information to Clientterminal 70 (step 37). For example, a user of a mobile station 1A aboarda train which is located at Long. 136° 15′ E., 35° 45′ N. and headingtoward South at a velocity of 46 Kilometers/hour. In this case, Locationinformation “Long. 136° 15′ E., 35° 45′ N.”, related information “46Km/hSouth”, and boarding information “Now boarding” are transmitted toClient terminal 70.

In case a user is not aboard, Location information server 60 does nottransmit the boarding information since Flag FLG in location responseRES 5 is set to “0”. As described above, people are able to obtainboarding information as well as location information of Mobile station1A by operating Client terminal 70 in this system.

3-3. Modification of the Third Embodiment

As described above, the system of the third embodiment is comprised byadding the system of the second embodiment to Location server 60 andClient terminal 70. However, it is possible to introduce a system inwhich Location server and Client terminal 70 are added to the system ofthe first embodiment.

In this system, when Location server 50A receives Location request REQ 5from Location information server 60, steps S5 trough S10 shown in FIG. 5are carried out. In this way Location server 50A obtains and transmitsto Location information server 60 Location area information INF. Next,Location information server 60 pages Mobile station 1A, on the basis ofthe Location area information INF, similarly to the third embodiment.

4. Fourth Embodiment 4-1. Configuration of a System

An information providing system based on the fourth embodiment is thesame as that of the third embodiment except for detailed function ofTraffic control device 30 and use of an object information server 40Binstead of 40A and Mobile station 1 instead of 1A. Specifically, Trafficcontrol device 30 transmits Movement information INFx only whenreceiving a request from Object information server 40B, similarly to thefirst embodiment. Object information server 40B has a management tableTBLk as shown in FIG. 13, differing from Object information server 40A.

FIG. 14 shows an example of information stored in Management table TBLk.Management table TBLk has a plurality of records Rc1, Rc2, . . . , eachstoring an Object ID number IDt, Movement information INFx, andtimestamp T. Timestamp T represents the time when Movement informationINFx is stored. Specifically, upon storing Movement information INFx,Control unit 51 obtains time from a timer not shown in the figure andwrites the time to Management table TBLk. For one example, Record Rc1indicates that Object location information INF1 “Long. 136° 15′ E., 35°45′ N.” is stored corresponding to Object ID number “A01234” at 13:00.

4-2. Operations of the System

Operations of the system will now be described referring to FIG. 15.FIG. 15 is a sequence diagram of the system. Steps S41 and S42 is thesame as steps S31 and S32 as described above, respectively.

Next, Location server 50B accesses Second location table TBL2. If ObjectID number IDt is stored corresponding to a Mobile ID number, Locationsever 50B sets the flag FLG to “1”. If the Object ID number is notstored, FLG is set to “0” (step S43). If Object ID number IDt is stored,Location server 50B transmits movement request REQ 8 including theObject ID number IDt to Object information server 40B (step S44).

Object information server 40B receives the Movement request REQ 8 andretrieves from Management table TBLk Movement information INFx andTimestamp T, each corresponding to the Object ID number IDt. If Movementinformation INFx is not stored in Management table TBLk or apredetermined time has elapsed since the time represented by TimestampT, Object information server 40B transmits a movement request REQ 9 toTraffic control device 30 (step S45).

Traffic control device 30 generates Movement information INFx about anObject 2 identified by the received Object ID number IDt and transmitsto Object information server 40B a movement response RES 9 including theINFx (step S47). Object information server 40B transmits to Locationserver 50B a movement response RES 8 including the Movement informationINFx (step S48).

If Movement information INFx is stored in Management table TBLk and apredetermined time has not elapsed since time T, Object informationserver 40B skips steps S45 through S47 and transmits a movement responseRES 8 to Location server 50B (step S48).

Location server 50B transmits a movement response RES 7 including theMovement information INFx to Location information server 60 (step S49).Location information server 60 receives Movement response RES7 andextracts INF2 from the Movement information INFx included in Movementresponse RES 7 to estimate a future location of Object 2. A specific wayof estimation is as follows:

Suppose that a user of a mobile station 1 is in a train whose Object IDnumber is “A01234” and Management table TBLk stores detailed informationshown in FIG. 14. When Location information server 60 receives alocation request REQ6 from Client terminal 70, steps S42 through S49 arecarried out as described above. As a result, Location information server60 obtains Related information INF2 “Azusa No. 2”. Next, Locationinformation server 60 estimates a future location of the train referringto timetable data stored in Hard disk 65. The estimated locationinformation generated by Location information server 60 includes, forexample, “arrive at Kofu in 18 minutes”.

Next Location information server 60 transmits to Client terminal 70 alocation response RES6 including Object location information INF1,Related information INF2, and Boarding information (step S50).Specifically, INF1 “Long. 136° 15′ E., 35° 45′ N.”, INF2 “Azusa No. 2”,and Estimated location information “This train will arrive at Kofu in 18minutes”, and Boarding information “Now boarding” is transmitted toClient terminal 70.

As described in this embodiment, a person is able to obtain the presentand future location of a mobile station by inputting a Mobile ID numberto Client terminal 70. In this system, location information of a Mobilestation can be obtained, even if the mobile station in Object 2 cannotcarry out radio communication with Base stations because Object 2 ismoving through a tunnel, for example.

In addition, the number of inquires to Traffic control device 30 forgetting the latest information on an object can be minimized. SinceObject information sever 40B checks Timestamp T, to judge whether toobtain the information from Traffic control device 30. In other words,the information is obtained efficiently and precisely.

4-3. Modification of the Fourth Embodiment

It is possible that Traffic control device 30 transmits the latestMovement information INFx to Movement information server 40B every timethe information INFx is updated. In this case, Location server is ableto obtain the latest information on Object 2 and needs not to refer toTimestamp T.

It is also possible that a person uses Client terminal 70, to designatethe detailed future location of a Mobile station. For example, a userinputs the desired time (an hour later, for example) in addition toMobile ID number. After reception of Object location information INF1,Related information INF2, and Estimated location information, theLocation information server 60 retrieves the estimated location of“Azusa No. 2” (near Matsumoto station, for example) referring to theschedule stored Hard disk 65. Retrieved information is transmitted toClient terminal 70.

5. Supplement

As described in the above embodiments, when a user of Mobile station 1gets aboard a train, Mobile station 1 receives Mobile ID number IDm fromTransmitting device TD and notifies Mobile ID number IDm and receivedObject ID number IDt to Mobile communication network NET via Basestation 3. However, it is possible that a device provided in Object 2transmits Mobile ID numbers IDms each of which is sent from Mobilestation 1 and Object ID number IDt, to mobile communication network NET.In this case, the device has the function of receiving Object ID numberIDt and Mobile ID number IDm. As an example, Transmitting device TD mayhave the function. The point is that Object ID number IDt and Mobile IDnumber IDm are transmitted together to Mobile communication network NET,when a user gets aboard.

Although the foregoing description provides many variations for use ofthe present invention, these enabling details should not be construed aslimiting in any way the scope of the invention, and it will be readilyunderstood that the present invention is susceptible to manymodifications, and equivalent implementations without departing fromthis scope and without diminishing its attendant advantages. It istherefore intended that the present invention is not limited to thedisclosed embodiments but should be defined in accordance with claimswhich follow.

1. (canceled)
 2. A location information provider comprising: a queryreceiver configured to receive an inquiry from a user terminal asking alocation of a mobile station, which is not the user terminal; a memorythat stores time schedules of transportations; a location queryerresponsive to the inquiry to find if the mobile station is situated on atransportation; a location estimator configured to determine, if themobile station is situated on a transportation, a future location of themobile station by referring to the time schedules stored in the memory;and a transmitter configured to transmit to the user terminal a responsewhich comprises the determined future location of the mobile station. 3.A location information provider according to claim 2, wherein thelocation queryer also finds, if the mobile station is situated on atransportation, a current location of the transportation and anidentification of the transportation, and the response comprises thecurrent location of the transportation and the identification of thetransportation.